JPH02177407A - Method of bonding core of transformer - Google Patents

Abstract

PURPOSE:To enable the temperature of adhesive to be elevated efficiently and in a short time so as to improve work efficiency and to see that it gets off without exerting an influence upon other constituent material by filling thermosetting adhesive which is conductive when the ends of cores are butted and bonded, and making them generate heat by current application through core parts so as to set the adhesive. CONSTITUTION:In case of butting the second foot 1b of a first core part 1 against the fourth foot 11b of a second core part 11 after inserting them in coils, and butting the first foot 1a of the first core part 1 against the third foot 11a of the second core part 11 so as to but the first and second ends 1a1 and 1b1 of the first core against the third and fourth ends 11a1 and 11b1 of the second core part 11 respectively, when butting the first and second ends 1a1 and 1b1 of the first core part 1 against the third and fourth ends 11a1 and 11b1 of the second core part 11 respectively, conductive thermosetting adhesives 3a and 3b are filled, and currents are applied to the thermosetting adhesives 3a and 3b through the first and second core parts 1 and 11 so as to generate heat, whereby the thermosetting adhesives 3a and 3b are set.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for bonding the core of a flyback transformer that supplies high voltage to a picture tube used in a television receiver or the like.

(Prior Art) Conventionally, the following two methods have been mainly used for bonding cores.

The first method is to use the joint surface of the core legs (the first
Legs 1a and lb of core 1 and leg 11a of core 11 shown in the figure,
After applying a mature hardening adhesive to the joint surface with the llb, and fixing the core in a U-shaped manner with a jig, put it in a drying oven.
After heating to 00 to 120° C. for 1 to 2 hours and cooling for about 4 hours, the tightening jig was removed.

The second method is to temporarily fix the core with a core band, apply adhesive to the joint surface of the core and the core band, and leave it for 3 to 10 hours to dry the adhesive naturally. It was glued together.

(Issue g to be solved by the present invention) The above-mentioned first method has the disadvantage that core tightening requires a jig and a drying oven, which increases manufacturing costs.
Further, since the heating time in the drying oven takes 1 to 2 hours and the subsequent cooling time takes about 4 hours, the production time is long and workability is poor. moreover,
Even if you want to increase the temperature of the drying oven to shorten the heating time in the drying oven, it may be difficult to increase the temperature due to differences in the heat resistance temperature and coefficient of thermal expansion of the other constituent materials of the flyback transformer, such as the insulating resin, diode, coil bobbin material, etc. There was a problem that the temperature could not be raised to 120° C. or higher because peeling at the interface would be a problem.

In addition, in the second method described above, a core band is required, and the adhesive must be handled to prevent it from adhering to anything else until it dries, and it takes 3 to 10 hours to dry. The problem was that it was difficult to handle and had extremely poor workability.

Therefore, in order to solve the above problems, the present invention has the following (1)
)~■ We propose methods.

(1) When adhering the core, a conductive mature adhesive is used, and the adhesive is cured using heat generated by electricity.

(2) When adhering the core, a conductive spacer and a mature hardening adhesive are used, and the adhesive is cured by utilizing the heat generated by the spacer due to electricity.

■ When adhering the core, a mature hardening adhesive is used, and electricity is applied to the core itself to generate heat and harden the adhesive.

(Means for Solving the Problem) As a means for achieving the above object, the following method for bonding the core of a transformer is provided.

(1) A first core portion comprising a first leg having a first tip portion and a second leg having a second tip portion and forming one of the cores; and a first core portion having a third tip portion. a second core part forming the other of the cores, the second core part having a third leg and a fourth leg having a fourth tip part; The fourth legs of the two core parts are each inserted into the coil and abutted, and the first leg of the first core part and the third leg of the second core part are abutted. ,
In the core bonding method for a transformer, the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and bonded, respectively. the first and second tip portions of the core portion of No. 1;
When the third and fourth tip portions of the second core portion are abutted and joined, a conductive mature hardening adhesive is filled and the adhesive is inserted through the first and second core portions, The transformer is characterized in that the first and second core portions are joined to form the core by applying electricity to the mature hardening type adhesive to generate heat and curing the mature hardening type adhesive. Core adhesion method.

(2) A first core portion comprising a first leg having a first tip portion and a second leg having a second tip portion and forming one of the cores; and a first core portion having a third tip portion. a second core part forming the other of the cores, the second core part having a third leg and a fourth leg having a fourth tip part; The fourth legs of the two core parts are each inserted into the coil and abutted, and the first leg of the first core part and the third leg of the second core part are abutted. ,
In the core bonding method for a transformer, the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and bonded, respectively. the first and second tip portions of the core portion of No. 1;
When the third and fourth tips of the second core are butted and joined, a conductive spacer is inserted and a ripe hardening adhesive is filled, and the first and second The first and second core parts are joined to form the core by applying electricity to the spacer through the core part to generate heat and harden the mature hardening adhesive. How to attach the transformer core.

(3) A first core portion comprising a first leg having a first tip portion and a second leg having a second tip portion and forming one of the cores; and a first core portion having a third tip portion. a second core part forming the other of the cores, the second core part having a third leg and a fourth leg having a fourth tip part; The fourth legs of the two core parts are each inserted into the coil and abutted, and the first leg of the first core part and the third leg of the second core part are abutted. ,
In the core bonding method for a transformer, the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and bonded, respectively. the first and second tip portions of the core portion of No. 1;
When the third and fourth tip portions of the second core portion are butted and joined, a mature hardening adhesive is filled and at least one of the first and second core portions is energized to generate heat. A method for bonding a core of a transformer, characterized in that the core is formed by joining the first and second core portions by curing the mature hardening type adhesive.

(Function) In the present invention, since the adhesive is heated directly from inside or from the vicinity, the temperature of the adhesive can be raised effectively and in a short time, and the ripening type adhesive is cured in a short time. As a result, workability is significantly improved, and since the heating is carried out locally, the constituent materials of the pond are not affected.

(Example) An example of the transformer core adhesion method of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram for explaining a flyback transformer manufactured using the transformer core bonding method of the present invention.

As shown in the figure, a pair of U-shaped core portions 1.11 forming a conductive core have legs 1a, 1b, lla, and 1, respectively.
lb, and the leg 1b of the core part 1 and the leg 11b of the core part 11 are inserted into the low voltage coil 4 of the flyback transformer. This low voltage coil 4 is inserted and fixed into a high voltage coil 5 of a flyback transformer.

Therefore, the leg 1b of the core part 1 and the leg 1b of the core part 11
1b is inserted so as to interlink with the low voltage coil 4 and high voltage coil 5 of the flyback transformer.

The tip portion 1a1 of the leg 1a of the core portion 1 and the core portion 11
A mature hardening type adhesive 3a is used to join the leg 11a of the leg 11a to the tip 11a1 of the core part 1.
b and the tip 11 of the leg 11b of the core part 11.
A mature hardening type adhesive 3b is also used for bonding with b1. At the time of this joining, due to circumstances in the production process, the above-mentioned mature hardening type adhesive 3a (3b) is applied to the above-mentioned tip 1a1 (tip
b1), tip portion 11aN tip portion 11b1), or tip portion 1a1 (tip portion 1b1).
It may be injected into the gap between the tip portion 11al (tip portion 11bl) and the tip portion 11al (tip portion 11bl).

The rectifier circuit 9 used in the above flyback transformer supplies an anode voltage to the cathode ray tube, and the insulating resin 6 such as epoxy resin connects the rectifier circuit 9, the low voltage coil 4, and the high voltage coil 5, respectively. Insulated.

Figure 2 shows the core part 1.11 glued with a ripe hardening adhesive.
It is a figure showing the state where electricity is supplied to the core consisting of. In this figure, the low-voltage coil 4, high-voltage coil 5, insulating resin 6, rectifier circuit 9, etc. shown in FIG. 1 are omitted, but in reality,
The legs 1b of the core part 1 and the legs 11b of the core part 11 are energized while being inserted therein. Also, the same components as those described above are denoted by the same reference numerals, and the explanation thereof will be omitted.

As shown in the figure, an electrode 7a is detachably attached to the rear end portion 1a2 of the leg 1a of the core portion 1 described above. Similarly,
The electrode 7b is attached to the rear end portion 1b2 of the leg 1b, and the electrode 7b is attached to the rear end portion 1b2 of the leg 1b.
At the rear end 11a2 of 1a @ [! 8 a, leg 11b
The tssb is removably attached to the rear end portion 11b2 of each. And these electrodes 7a, 7b, 8a,
Connect the power supply 10 to 8b. The power supply 10 shown in the figure is a DC power supply, but it may also be an AC power supply.
If there are large variations in the conductivity of No. 1, using a constant current power source instead of a constant voltage power source will reduce the variation in the curing action of the mature hardening adhesive.

The above-mentioned mature hardening adhesives 3a and 3b are thermosetting silicone rubber adhesives used as adhesive sealants for electronics having almost no conductivity and a volume resistivity of 2×1015 Ω·1, such as those manufactured by Toshiba Silicon Co., Ltd. Produced by mixing a conductive substance, such as carbon, into the electronics adhesive sealant rTSE322-BJ.
It is an electrically conductive adhesive with a volume resistivity of 101 to 107Ω.

In this way, the tips 1a1 of the legs 1a of the core section 1 and the tips 11a1 of the legs 11a of the core section 11 are bonded together with the mature hardening adhesive 3a, and the tips of the legs 1b of the core section 1 are bonded together. 1b1 and the tips 11b1 of the legs 11b of the core part 11 are bonded with a ripe hardening adhesive 3b, and then the electrodes 7a, 7b, 8a, 8
By applying electricity to b, the ripe hardening adhesives 3a and 3b
is heated and hardened, and the legs 1a and lb of the core part 1 and the core part 1
The legs 11a and 11b of 1 are electrically and mechanically firmly connected, and the core shown in FIG. 1 can be formed.

Above, when adhering the core, it was described that conductive mature hardening adhesives 3a and 3b were used and the adhesive was cured using heat generated by electricity. When adhering the cores, a conductive spacer and a mature curing adhesive are used, and the adhesive is cured by utilizing the heat generated by the spacer when energized.

As shown in FIGS. 1 and 2, these electrically conductive spacers 2a and 2b are located between the tip portion 1a1 of the leg 1a of the core portion 1 and the tip portion 11a1 of the leg 11a of the core portion 11. A spacer 2a is inserted together with a mature hardening type adhesive 3a, and the tip portion 1 of the leg 1b of the core portion 1 is inserted into the spacer 2a.
A spacer 2b is inserted between b1 and the tip portion 11b1 of the leg 11b of the core portion 11 together with a mature hardening adhesive 3b.

Then, the above-mentioned conductive mature hardening adhesive 3a
, 3b, the legs 1a, lb of the core part 1 are cured by using heat generated by the spacers 2a, 2b by energization to harden the mature hardening type adhesives 3a, 3b. and the legs 11a and flb of the core portion 11 are electrically and mechanically strongly coupled to form the core shown in FIG. 1.

Note that in this case, when the mature hardening adhesives 3a and 3b are conductive mature hardening adhesives, non-conductive spacers may be used in place of the conductive spacers 2a and 2b described above. Of course.

In the above-mentioned method, electricity is applied through the two pairs of electrodes 7a, 7b, 8a, 8b attached to the core part 1.11 to generate heat in the ripe hardening adhesives 3a, 3b or the spacers 2a, 2b. The above description describes curing this and adhering the core part 1.11. Using a pair of electrodes 7a and 7b, electricity is applied only to the core part 1, causing the mature hardening adhesive to generate heat. It is also possible to harden this and glue the core part 1.11.

That is, the ripe hardening adhesives 3a, 3b and the spacers 2a, 2b
If both of the electrodes do not have conductivity, as shown in FIG. By doing so, the core part 1 generates heat, and the mature hardening adhesives 3a and 3b are hardened by this heat and fixed to the core part 11.

The transformer core bonding method of the present invention described above not only accelerates the curing of the adhesive, but also greatly improves the work of adjusting the primary inductance of the flyback transformer to the standard.

In other words, when attaching a core to a flyback transformer, there are large variations in the magnetic permeability of the core (±20%) and variations in the thickness of the spacer (±5%), so the primary inductance of the flyback transformer is set to the standard (±5%). %) requires work such as replacing spacers, which takes a considerable amount of time. However, in the transformer core adhesion method of the present invention, the core bonding surface is a cured type that has conductivity. After applying adhesive and assembling this into the flyback transformer, change the gap length of the core with a jig etc. while measuring the -order inductance, and when the primary inductance falls within the standard, energize the core. By heating and curing the adhesive, workability can be greatly improved.

Also, as the conductivity of the adhesive and spacer increases, heat generation due to eddy currents of the magnetic flux passing through the adhesive and spacer increases, so it is necessary to set the conductivity of the adhesive and spacer to a value where heat generation due to eddy current does not become a problem. , the generation of eddy currents must be suppressed as much as possible.

Since eddy currents are generated in a plane orthogonal to the magnetic flux, the generation of eddy currents can be prevented if at least one of the following two conditions is satisfied.

■Reducing the conductivity in a plane approximately perpendicular to the direction of magnetic flux passage.

■Reducing the area of the conductor in a plane substantially perpendicular to the magnetic flux passing direction.

As an example in which both of these conditions are satisfied, as shown in FIG. 3(A), the insulator 12 such as a film is arranged so that its longitudinal direction is oriented in the same direction as the magnetic flux direction (in the thickness direction of the spacer 2C).
If a spacer 2C is used in which a linear conductor 13 is mixed, or if a spacer 2d is used in which a spherical conductor 14 having a diameter approximately equal to the thickness of the spacer 2d is mixed in an insulator 12 as shown in FIG. 3(B). The generation of eddy currents can be prevented.

The embodiments described above are merely examples, and it goes without saying that various modifications may be made without departing from the spirit of the invention.

(Effects of the Invention) The transformer core bonding method of the present invention heats the adhesive directly from inside or from the vicinity, so the temperature of the adhesive can be raised effectively and in a short time. can be cured in a short time.

Therefore, compared to the first conventional method, the work of loading and unloading the drying oven can be omitted, and the heating and cooling time can be significantly shortened.

Further, the -order inductance can be easily adjusted, and the core bonding process can be carried out online, so that workability is significantly improved.

Furthermore, core tightening eliminates the need for jigs and drying ovens, making it possible to reduce costs.

The conductive ripe hardening adhesive can be used even when there is no gap between the joint surfaces of the first core part and the second core part due to the design. If there is a gap between the bonding surfaces of the parts, an ordinary mature hardening type adhesive can be used by using a conductive spacer. Furthermore, by supplying electricity to at least one of the first core portion and the second core portion, the ripe hardening adhesive can be cured in a short time regardless of the conductivity of the hardening adhesive or the spacer. There is an effect.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the main parts of a flyback transformer using an embodiment of the transformer core bonding method of the present invention, FIG. 2 is a sectional view of the main parts of the flyback transformer with the coil section omitted, and FIG. A> and (B) are cross-sectional views of a spacer, and FIG. 4 is a cross-sectional view of essential parts of a flyback transformer using an embodiment of the present invention. 1... First core part, 11...・Second core part, 1a
...first leg, 1b...second leg, 11a...third leg, llb...fourth leg, lal...first tip, lbl...th 2 tip, 11a1...3rd
Tip part, 11b1...Fourth tip part, 1 a2.1
b2.11 a2.11 b2--End portion of core leg, 2a, 2b, 2c, 2ri--Spacer, 3a,
3b...Mature hardening adhesive, ? a, 7b, 8a, 8b=... electrode, 10... power supply,
12... Insulator, 13... Linear conductor, 14... Spherical conductor.

Claims (3)

[Claims] (1) A first core portion comprising a first leg having a first tip portion and a second leg having a second tip portion and forming one of the cores; and a first core portion having a third tip portion. and a second core part forming the other of the cores, the second core part having a third leg and a fourth leg having a fourth tip part, and a second core part forming the other of the cores; The fourth legs of the two core parts are each inserted into the coil and abutted, and the first leg of the first core part and the third leg of the second core part are abutted. In the transformer core bonding method, the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and bonded, respectively. When the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and joined, a conductive thermosetting adhesive is used. The thermosetting adhesive is filled with electricity through the first and second core portions to generate heat, and the mature hardening adhesive is cured, thereby forming the first and second cores. A method for bonding a core of a transformer, the method comprising: forming the core by bonding parts. (2) a first core portion comprising a first leg having a first tip portion and a second leg having a second tip portion and forming one of the cores; and a first core portion having a third tip portion. and a second core part forming the other of the cores, the second core part having a third leg and a fourth leg having a fourth tip part, and a second core part forming the other of the cores; The fourth legs of the two core parts are each inserted into the coil and abutted, and the first leg of the first core part and the third leg of the second core part are abutted. In the transformer core bonding method, the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and bonded, respectively. When abutting and joining the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion, a conductive spacer is inserted and The spacer is filled with a thermosetting adhesive, and the spacer is energized to generate heat through the first and second core portions, thereby curing the thermosetting adhesive. A method for bonding a core of a transformer, characterized in that the core is formed by bonding core portions. (3) a first core portion comprising a first leg having a first tip portion and a second leg having a second tip portion and forming one of the cores; and a first core portion having a third tip portion. and a second core part forming the other of the cores, the second core part having a third leg and a fourth leg having a fourth tip part, and a second core part forming the other of the cores; The fourth legs of the two core parts are each inserted into the coil and abutted, and the first leg of the first core part and the third leg of the second core part are abutted. In the transformer core bonding method, the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and bonded, respectively. When the first and second tip portions of the first core portion and the third and fourth tip portions of the second core portion are butted and joined, filling with a thermosetting adhesive, By supplying electricity to at least one of the first and second core parts to generate heat and curing the thermosetting adhesive,
A method for bonding a core of a transformer, characterized in that the core is formed by bonding the first and second core portions.